When manufacturing household cold appliances, such as refrigerators, comprising also pantries and wine coolers, and freezers, comprising also chest freezers, which are in the form of an openable cabinet and which are primarily adapted for domestic use but also can be used in for example restaurants and laboratories, hereinafter referred to as cold appliances for sake of simplicity, it is common practice to locate the production rather close to the customers, since the costs of transportation are considerable. This results in a comparatively large amount of production sites. It is desirable to rather have a few large production plants, and then distribute the products from these plants to the rest of the world. In this way it is possible to take advantage of large-scale benefits. For example, one problem associated with transporting cold appliances is that they represent bulky products containing a lot of air, which has to effect that the transport costs per weight unit will be considerable. It has been suggested to manufacture cold appliances in a modular fashion, such that the products can be transported in a disassembled state and assembled at the place of installation or at a nearby store, an assembling plant or other service facility. However, no functional modular system has ever been developed for such products. This is due to the various requirements that the cabinet must fulfil. For instance the cabinet must be constructed to be easily assembled to form a rigid and resistant cabinet having good heat insulating properties and being substantially impermeable to moisture migration as well as having an aesthetically attractive appearance. Additionally, a cooling cabinet contains a lot of technical equipment for performing different functions. This equipment, when having the present structure, is difficult to provide as modules which are easy to assemble and interconnect.
Another problem associated with conventional manufacturing of cold appliances, is that it involves high investment costs for development of product lines and the like. This results in a very poor flexibility, primarily with regard to the possibility of producing cold appliances having different dimensions and variable equipment options in small series. Normally, new product designs necessitate large production series to be feasible for economic reasons. This also has to effect that the producers are unwilling to develop products having a new approach since the economic risk is so large, with a uniformed product line as a result, alternatively that a more odd product will be very expensive to produce and purchase.
Another problem associated with a modular cold appliance is how to arrange a condensation preventing device at the front of the cold compartment(-s). In a non-module cold appliance that is conventionally manufactured, as disclosed in U.S. Pat. No. 6,666,043, a condensation preventing device is arranged as a heat carrier tube extending along a front frame portion, which surrounds the cold compartment(-s) of the cabinet. The tube is filled with a heat carrier fluid, and is provided with a heat exchanger box, which is placed under a compressor included in the cooling system of the cold appliance. In U.S. Pat. No. 6,666,043 there is no information about how the tube is actually mounted at the front frame portion, but on the other hand there is no problem involved in the mounting thereof. To the contrary, when the cold appliance is not completed in the originating factory, but delivered in pieces and assembled on arrival, a problem arises of how to manufacture the pieces in order to facilitate the assembly.
When building a cold appliance in the conventional way, where the cabinet is built on site it is easy to obtain complex built in functions. However, when providing separate parts which are going to be mounted later on, new solutions are needed. One problem to be solved is how to obtain the complex interface between the cabinet and the door, where for example the above mentioned condensation preventing device is to be mounted.
In conventional cold appliances the evaporator is formed as a rather flat and rectangular device, which is mounted inside of the cabinet. The present invention is within the field of dynamic cooling, where the cooling module is a separate module which comprises all cooling devices, including the evaporator, and is subsequently assembled with the cabinet. Then the cooled air is circulated within the cabinet in order to cool the food. The air is cooled by having it pass through or around the evaporator, depending on its construction, by means of a fan. Then the conventional rectangular and rather flat shape is not optimal.
When manufacturing separate cabinet panels which are to be subsequently mounted, instead of manufacturing a cabinet shell and fill it with foam, it should be possible, and would be desirable to find a way to automate this manufacture, at least for some of the types panels involved.
In a cold appliance where the cooling effect is generated by a cooling module according to a self-contained type, and is distributed by an air flow inside the cabinet, it is a desire to make the cooling module compact. In order to make the cooling module as compact as possible it would be desirable to arrange the largest parts, i.e. the evaporator and the compressor beside each other, though of course thermally insulated from each other. This placement may result in that at least a part of the evaporator is positioned lower than an upper portion of the compressor. This mutual positioning will have some negative impact on the defrost system, i.e. the system which effects warming of the evaporator for melting of frost and ice aggregated thereon, drainage of the resulting defrost water, and evaporation of the defrost water. Conventionally, the defrost water is evaporated from a basin on top of the compressor as the warm compressor casing is heating up the water. The water is led by gravity from the evaporator to the basin by a tube or the like. However, when the evaporator, at least partly, is positioned lower than the compressor, this is not a possible solution. Consequently, there is a need of another solution.
Furthermore, when placing the cooling module below the cabinet, which is desirable in many applications, there are air ducts for circulating air to and from the cabinet may cause warming of the cold compartment of the cabinet when defrosting the evaporator, due to warm air rising, by natural convection, through the air duct normally delivering cold air. A straight forward solution would be to restrict this heat leakage by providing air shutters in the air ducts, which will close the air ducts during the defrost periods. A drawback with such a solution is that it necessitates the arrangement of more movable parts as well as control equipment, which will increase the costs for the cooling module.
In a modular cold appliance where a system for forced air circulation in the cold compartment(s) of the cabinet is necessary there arises a need for providing an efficient circulation of the air.